If you have those locking bolts top and bottom, they should prevent the door being lifted off its tracks, and should hold it even if the cylinder of the multipoint is attacked (there are various ways to defeat a Eurocylinder). take the keys out, and hang them on a cup hook away from the door (you do not need a key to lock them,) and also the main key.
If you need another lock, get a pair with the same key.
IMO patio doors do not need a keyhole on the outside.
I think the doors are Aluminium, which is stronger than plastic.
The glass is probably toughened, which is easy to break into tiny pieces.
I quite like a metal Venetian blind inside glass doors, it makes a tremendous noise if someone tries to get through it.
I have a room with patio doors, it has a substantial fire door into the rest of the house, fitted with a 5-lever BS deadlock, and an intruder alarm sensor. Mine are fitted with laminated glass, which is perhaps excessive. There are no portable valuables visible to someone outside.